Annotation of GNUtools/cc/gmon.c, revision 1.1

1.1     ! root        1: /*-
        !             2:  * Copyright (c) 1991 The Regents of the University of California.
        !             3:  * All rights reserved.
        !             4:  *
        !             5:  * Redistribution and use in source and binary forms, with or without
        !             6:  * modification, are permitted provided that the following conditions
        !             7:  * are met:
        !             8:  * 1. Redistributions of source code must retain the above copyright
        !             9:  *    notice, this list of conditions and the following disclaimer.
        !            10:  * 2. Redistributions in binary form must reproduce the above copyright
        !            11:  *    notice, this list of conditions and the following disclaimer in the
        !            12:  *    documentation and/or other materials provided with the distribution.
        !            13:  * 3. All advertising materials mentioning features or use of this software
        !            14:  *    must display the following acknowledgement:
        !            15:  *     This product includes software developed by the University of
        !            16:  *     California, Berkeley and its contributors.
        !            17:  * 4. Neither the name of the University nor the names of its contributors
        !            18:  *    may be used to endorse or promote products derived from this software
        !            19:  *    without specific prior written permission.
        !            20:  *
        !            21:  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
        !            22:  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
        !            23:  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
        !            24:  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
        !            25:  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
        !            26:  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
        !            27:  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
        !            28:  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
        !            29:  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
        !            30:  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
        !            31:  * SUCH DAMAGE.
        !            32:  */
        !            33: 
        !            34: #ifndef lint
        !            35: static char sccsid[] = "@(#)gmon.c     5.3 (Berkeley) 5/22/91";
        !            36: #endif /* not lint */
        !            37: 
        !            38: #if 0
        !            39: #include <unistd.h>
        !            40: 
        !            41: #endif
        !            42: #ifdef DEBUG
        !            43: #include <stdio.h>
        !            44: #endif
        !            45: 
        !            46: #include "gmon.h"
        !            47: 
        !            48: extern mcount() asm ("mcount");
        !            49: extern char *minbrk asm ("minbrk");
        !            50: 
        !            51:     /*
        !            52:      * froms is actually a bunch of unsigned shorts indexing tos
        !            53:      */
        !            54: static int             profiling = 3;
        !            55: static unsigned short  *froms;
        !            56: static struct tostruct *tos = 0;
        !            57: static long            tolimit = 0;
        !            58: static char            *s_lowpc = 0;
        !            59: static char            *s_highpc = 0;
        !            60: static unsigned long   s_textsize = 0;
        !            61: 
        !            62: static int     ssiz;
        !            63: static char    *sbuf;
        !            64: static int     s_scale;
        !            65:     /* see profil(2) where this is describe (incorrectly) */
        !            66: #define                SCALE_1_TO_1    0x10000L
        !            67: 
        !            68: #define        MSG "No space for profiling buffer(s)\n"
        !            69: 
        !            70: monstartup(lowpc, highpc)
        !            71:     char       *lowpc;
        !            72:     char       *highpc;
        !            73: {
        !            74:     int                        monsize;
        !            75:     char               *buffer;
        !            76:     register int       o;
        !            77: 
        !            78:        /*
        !            79:         *      round lowpc and highpc to multiples of the density we're using
        !            80:         *      so the rest of the scaling (here and in gprof) stays in ints.
        !            81:         */
        !            82:     lowpc = (char *)
        !            83:            ROUNDDOWN((unsigned)lowpc, HISTFRACTION*sizeof(HISTCOUNTER));
        !            84:     s_lowpc = lowpc;
        !            85:     highpc = (char *)
        !            86:            ROUNDUP((unsigned)highpc, HISTFRACTION*sizeof(HISTCOUNTER));
        !            87:     s_highpc = highpc;
        !            88:     s_textsize = highpc - lowpc;
        !            89:     monsize = (s_textsize / HISTFRACTION) + sizeof(struct phdr);
        !            90:     buffer = sbrk( monsize );
        !            91:     if ( buffer == (char *) -1 ) {
        !            92:        write( 2 , MSG , sizeof(MSG) );
        !            93:        return;
        !            94:     }
        !            95:     froms = (unsigned short *) sbrk( s_textsize / HASHFRACTION );
        !            96:     if ( froms == (unsigned short *) -1 ) {
        !            97:        write( 2 , MSG , sizeof(MSG) );
        !            98:        froms = 0;
        !            99:        return;
        !           100:     }
        !           101:     tolimit = s_textsize * ARCDENSITY / 100;
        !           102:     if ( tolimit < MINARCS ) {
        !           103:        tolimit = MINARCS;
        !           104:     } else if ( tolimit > 65534 ) {
        !           105:        tolimit = 65534;
        !           106:     }
        !           107:     tos = (struct tostruct *) sbrk( tolimit * sizeof( struct tostruct ) );
        !           108:     if ( tos == (struct tostruct *) -1 ) {
        !           109:        write( 2 , MSG , sizeof(MSG) );
        !           110:        froms = 0;
        !           111:        tos = 0;
        !           112:        return;
        !           113:     }
        !           114:     minbrk = sbrk(0);
        !           115:     tos[0].link = 0;
        !           116:     sbuf = buffer;
        !           117:     ssiz = monsize;
        !           118:     ( (struct phdr *) buffer ) -> lpc = lowpc;
        !           119:     ( (struct phdr *) buffer ) -> hpc = highpc;
        !           120:     ( (struct phdr *) buffer ) -> ncnt = ssiz;
        !           121:     monsize -= sizeof(struct phdr);
        !           122:     if ( monsize <= 0 )
        !           123:        return;
        !           124:     o = highpc - lowpc;
        !           125:     if( monsize < o )
        !           126: #ifndef hp300
        !           127:        s_scale = ( (float) monsize / o ) * SCALE_1_TO_1;
        !           128: #else /* avoid floating point */
        !           129:     {
        !           130:        int quot = o / monsize;
        !           131: 
        !           132:        if (quot >= 0x10000)
        !           133:                s_scale = 1;
        !           134:        else if (quot >= 0x100)
        !           135:                s_scale = 0x10000 / quot;
        !           136:        else if (o >= 0x800000)
        !           137:                s_scale = 0x1000000 / (o / (monsize >> 8));
        !           138:        else
        !           139:                s_scale = 0x1000000 / ((o << 8) / monsize);
        !           140:     }
        !           141: #endif
        !           142:     else
        !           143:        s_scale = SCALE_1_TO_1;
        !           144:     moncontrol(1);
        !           145: }
        !           146: 
        !           147: _mcleanup()
        !           148: {
        !           149:     int                        fd;
        !           150:     int                        fromindex;
        !           151:     int                        endfrom;
        !           152:     char               *frompc;
        !           153:     int                        toindex;
        !           154:     struct rawarc      rawarc;
        !           155: 
        !           156:     moncontrol(0);
        !           157:     fd = creat( "gmon.out" , 0666 );
        !           158:     if ( fd < 0 ) {
        !           159:        perror( "mcount: gmon.out" );
        !           160:        return;
        !           161:     }
        !           162: #   ifdef DEBUG
        !           163:        fprintf( stderr , "[mcleanup] sbuf 0x%x ssiz %d\n" , sbuf , ssiz );
        !           164: #   endif DEBUG
        !           165:     write( fd , sbuf , ssiz );
        !           166:     endfrom = s_textsize / (HASHFRACTION * sizeof(*froms));
        !           167:     for ( fromindex = 0 ; fromindex < endfrom ; fromindex++ ) {
        !           168:        if ( froms[fromindex] == 0 ) {
        !           169:            continue;
        !           170:        }
        !           171:        frompc = s_lowpc + (fromindex * HASHFRACTION * sizeof(*froms));
        !           172:        for (toindex=froms[fromindex]; toindex!=0; toindex=tos[toindex].link) {
        !           173: #          ifdef DEBUG
        !           174:                fprintf( stderr ,
        !           175:                        "[mcleanup] frompc 0x%x selfpc 0x%x count %d\n" ,
        !           176:                        frompc , tos[toindex].selfpc , tos[toindex].count );
        !           177: #          endif DEBUG
        !           178:            rawarc.raw_frompc = (unsigned long) frompc;
        !           179:            rawarc.raw_selfpc = (unsigned long) tos[toindex].selfpc;
        !           180:            rawarc.raw_count = tos[toindex].count;
        !           181:            write( fd , &rawarc , sizeof rawarc );
        !           182:        }
        !           183:     }
        !           184:     close( fd );
        !           185: }
        !           186: 
        !           187: mcount()
        !           188: {
        !           189:        register char                   *selfpc;
        !           190:        register unsigned short         *frompcindex;
        !           191:        register struct tostruct        *top;
        !           192:        register struct tostruct        *prevtop;
        !           193:        register long                   toindex;
        !           194: 
        !           195:        /*
        !           196:         *      find the return address for mcount,
        !           197:         *      and the return address for mcount's caller.
        !           198:         */
        !           199: 
        !           200:        /* selfpc = pc pushed by mcount call.
        !           201:           This identifies the function that was just entered.  */
        !           202:        selfpc = (void *) __builtin_return_address (0);
        !           203:        /* frompcindex = pc in preceding frame.
        !           204:           This identifies the caller of the function just entered.  */
        !           205:        frompcindex = (void *) __builtin_return_address (1);
        !           206:        /*
        !           207:         *      check that we are profiling
        !           208:         *      and that we aren't recursively invoked.
        !           209:         */
        !           210:        if (profiling) {
        !           211:                goto out;
        !           212:        }
        !           213:        profiling++;
        !           214:        /*
        !           215:         *      check that frompcindex is a reasonable pc value.
        !           216:         *      for example:    signal catchers get called from the stack,
        !           217:         *                      not from text space.  too bad.
        !           218:         */
        !           219:        frompcindex = (unsigned short *)((long)frompcindex - (long)s_lowpc);
        !           220:        if ((unsigned long)frompcindex > s_textsize) {
        !           221:                goto done;
        !           222:        }
        !           223:        frompcindex =
        !           224:            &froms[((long)frompcindex) / (HASHFRACTION * sizeof(*froms))];
        !           225:        toindex = *frompcindex;
        !           226:        if (toindex == 0) {
        !           227:                /*
        !           228:                 *      first time traversing this arc
        !           229:                 */
        !           230:                toindex = ++tos[0].link;
        !           231:                if (toindex >= tolimit) {
        !           232:                        goto overflow;
        !           233:                }
        !           234:                *frompcindex = toindex;
        !           235:                top = &tos[toindex];
        !           236:                top->selfpc = selfpc;
        !           237:                top->count = 1;
        !           238:                top->link = 0;
        !           239:                goto done;
        !           240:        }
        !           241:        top = &tos[toindex];
        !           242:        if (top->selfpc == selfpc) {
        !           243:                /*
        !           244:                 *      arc at front of chain; usual case.
        !           245:                 */
        !           246:                top->count++;
        !           247:                goto done;
        !           248:        }
        !           249:        /*
        !           250:         *      have to go looking down chain for it.
        !           251:         *      top points to what we are looking at,
        !           252:         *      prevtop points to previous top.
        !           253:         *      we know it is not at the head of the chain.
        !           254:         */
        !           255:        for (; /* goto done */; ) {
        !           256:                if (top->link == 0) {
        !           257:                        /*
        !           258:                         *      top is end of the chain and none of the chain
        !           259:                         *      had top->selfpc == selfpc.
        !           260:                         *      so we allocate a new tostruct
        !           261:                         *      and link it to the head of the chain.
        !           262:                         */
        !           263:                        toindex = ++tos[0].link;
        !           264:                        if (toindex >= tolimit) {
        !           265:                                goto overflow;
        !           266:                        }
        !           267:                        top = &tos[toindex];
        !           268:                        top->selfpc = selfpc;
        !           269:                        top->count = 1;
        !           270:                        top->link = *frompcindex;
        !           271:                        *frompcindex = toindex;
        !           272:                        goto done;
        !           273:                }
        !           274:                /*
        !           275:                 *      otherwise, check the next arc on the chain.
        !           276:                 */
        !           277:                prevtop = top;
        !           278:                top = &tos[top->link];
        !           279:                if (top->selfpc == selfpc) {
        !           280:                        /*
        !           281:                         *      there it is.
        !           282:                         *      increment its count
        !           283:                         *      move it to the head of the chain.
        !           284:                         */
        !           285:                        top->count++;
        !           286:                        toindex = prevtop->link;
        !           287:                        prevtop->link = top->link;
        !           288:                        top->link = *frompcindex;
        !           289:                        *frompcindex = toindex;
        !           290:                        goto done;
        !           291:                }
        !           292: 
        !           293:        }
        !           294: done:
        !           295:        profiling--;
        !           296:        /* and fall through */
        !           297: out:
        !           298:        return;         /* normal return restores saved registers */
        !           299: 
        !           300: overflow:
        !           301:        profiling++; /* halt further profiling */
        !           302: #   define     TOLIMIT "mcount: tos overflow\n"
        !           303:        write(2, TOLIMIT, sizeof(TOLIMIT));
        !           304:        goto out;
        !           305: }
        !           306: 
        !           307: /*
        !           308:  * Control profiling
        !           309:  *     profiling is what mcount checks to see if
        !           310:  *     all the data structures are ready.
        !           311:  */
        !           312: moncontrol(mode)
        !           313:     int mode;
        !           314: {
        !           315:     if (mode) {
        !           316:        /* start */
        !           317:        profil(sbuf + sizeof(struct phdr), ssiz - sizeof(struct phdr),
        !           318:                (int)s_lowpc, s_scale);
        !           319:        profiling = 0;
        !           320:     } else {
        !           321:        /* stop */
        !           322:        profil((char *)0, 0, 0, 0);
        !           323:        profiling = 3;
        !           324:     }
        !           325: }
        !           326: 

unix.superglobalmegacorp.com

This archive runs on limited infrastructure. Preserving old code on modern bandwidth. Automated agents are requested to crawl responsibly.